Method and device for transporting packaging bags for liquid or pasty products having a weld-in closure

ABSTRACT

For transporting packaging bags ( 1 ), e.g. from a production facility to further processing, e.g. for being filled, the packaging bags ( 1 ) are connected to at least one flexible strip ( 13, 14 ). To this end, the packaging bags ( 1 ) are delivered one after another to a loading device where they are supported by their weld-in closures ( 4 ) on supporting and guiding means ( 9 ) and moved along these supporting and guiding means ( 9; 10 ). On the latter, the weld-in closures are connected to the strip ( 13, 14 ), e.g. by welding.

The present invention relates to a method and a device according to the preambles of independent claims 1 and 10.

Transport units for packaging bags are known in the art, e.g. from WO2012/028980, where a track with flat bags lined up thereon is provided for the transport from the production site of the bags to the filling site of the bags. Such bags are suitable particularly for liquids and among these particularly for highly viscous liquids such as creams, yogurts, honey, fruit juices, etc. According to this publication, today's packaging technology is based on the assumption that the relevant bags are manufactured at a production site and are then transported to a filling site. It is therefore essential with regard to this technology that the logistics costs incurred may be kept as low as possible. By providing tracks, the bags can be delivered to the filling station in such an order and orientation as to be directly utilizable, and in a separated state.

In WO2012/028980 it has been recognized that such a logistics container filled with transport units entails a considerable space consumption. The space required on the tracks is not primarily determined by the bag material but by the weld-in closures. Therefore it is suggested in this reference to place tracks opposite each other in a logistics container so that the bags of one track and those of the opposite track alternately interlock. In this manner, almost twice the number of tracks and bags can be transported in a given logistics container.

Using tracks is associated with considerable complexity, and their operation can only partly be automated. Thus, after having been loaded onto the tracks, the bags have to be secured by means of clips or the like so that they will not fall out while the tracks are being manipulated. The logistics containers are loaded manually, especially in the case of the aforementioned interlocked placement. Likewise, removing the tracks from the logistics containers at the filling site and loading the tracks into the filling installation is largely achieved manually. Afterwards, the empty tracks have to be returned to the production site, which is not only associated to considerable logistical requirements but also to hygienic problems.

In order to increase the automation level when tracks are being used, cages that are loaded and unloaded by robots have recently been introduced as logistics containers.

This method is not only complicated and expensive but also involves the problem that not only the tracks but also the empty cages have to be returned to the production site.

The reference EP 0 171 550 A1 discloses a system for handling pharmaceutical containers where groups of containers are retained by a flexible strip engaging the container closures by means of corresponding depressions.

On the background of this prior art, it is the object of the invention to suggest a method for transporting packaging bags for liquid or pasty products having weld-in closures with pouring openings where both the logistical efforts for the transport between the production site and the filling site and the space requirements are significantly reduced.

According to the invention, this object is achieved by the features defined in the characterizing parts of the independent claims.

This inventive solution offers the advantage that the connection to the strip can be automated thanks to the supporting and guiding means. The application of a strip allows joining a very large number of packaging bags to form one transport unit.

Particular embodiments are indicated in the dependent claims.

Examples of preferred embodiments of the invention will be described hereinafter with reference to the drawings which merely serve for illustrative purposes and shall not be construed as limiting. The figures in the drawings show:

FIG. 1 a view sectioned along line I-I in FIG. 2 of a first exemplary embodiment of a loading device;

FIG. 2 a top view of the device of FIG. 1;

FIG. 3 a view sectioned along line III-III in FIG. 4 of a second exemplary embodiment of a loading device;

FIG. 4 a top view of the arrangement of FIG. 3;

FIG. 5 a top view of a strip with perforations for transport in a defined position;

FIG. 6 a cross-sectional view of the strip sectioned along line VI-VI in FIG. 5 where embossings for stiffening the strip are visible;

FIG. 7 a top view of a strip with cavities for a fluid-supported stiffening of the strip;

FIG. 8 a cross-sectional view of the strip sectioned along line VII-VII in FIG. 7;

FIG. 9 a view sectioned along line IX-IX in FIG. 10 of a third exemplary embodiment of a loading device;

FIG. 10 a top view of the arrangement of FIG. 9;

FIG. 11 a view sectioned along line XI-XI in FIG. 12 of a first exemplary embodiment of a separating device for separating the strips from the flanges by tearing;

FIG. 12 a top view of the arrangement of FIG. 11;

FIG. 13 a view sectioned along line XIII-XIII in FIG. 14 of a second exemplary embodiment of a separating device;

FIG. 14 a top view of the arrangement of FIG. 13;

FIG. 15 a top view of a transport aid gripping a weld-in closure;

FIG. 16 a view in the direction of arrow XVI in FIG. 15;

FIG. 17 a schematic perspective drawing of an installation for filling packaging bags and of a third exemplary embodiment of a separating device.

FIG. 1 shows a view sectioned along line I-I in FIG. 2 of a first embodiment of a loading device for connecting flexible packaging bags 1 to two parallel strips 13, 14. FIG. 2 shows a top view of this loading device. Packaging bags 1 are e.g. directly supplied from a production facility and can therefore be automatically transferred to the loading device in the depicted defined orientation. The illustrated packaging bag 1 is formed of two film layers 2 that are joined by weld seams 3, a weld-in closure part 4 being arranged between the film layers in an upper area of FIG. 1. In this exemplary embodiment, weld-in closure 4 has two guiding flanges 7 extending to the left and to the right in FIGS. 1 and 2 in parallel to film layers 2. At the top of weld-in closure 4, a pouring spout 5 with a pouring opening 6 is integrally formed. The latter may also be used for filling packaging bag 1 and may subsequently be closed by means of a non-represented cap after packaging bag 1 has been filled. Guiding flanges 7 are supported on two parallelly arranged guiding rails 9 which leave a gap 11 for the passage of weld-in closures 4 between them. Guiding rails 9 are provided with longitudinal grooves in which guiding flanges 7 engage, thereby preventing an involuntary lifting off of weld-in closures 4. Two flexible strips 13, 14 are connected to guiding flanges 7.

The flexible strips may consist of usual synthetic foils as they are used in the field of flexible packages, but other materials such as textiles, metals, paper and so on may be contemplated as well. As synthetic materials, particularly those from the polyethylene (PE), polyethylene terephthalate (PETP), polypropylene (PP), and polyamide (PA) groups may be used. If strips 13, 14 are connected to guiding flanges 7 by welding, they preferably consist of two layers so that one layer can be welded to guiding flange 7 and the second, heat-resistant layer will withstand the separating operation described below without being damaged and thus prevents that the strip is torn while being detached. In the example according to FIGS. 1 and 2, two different fastening modes of guiding flanges 7 to strips 13, 14 are illustrated, which would probably not be implemented in this manner, of course. In practice, both strips 13, 14 would rather be connected to guiding flanges 7 in the same manner. On the left in FIG. 1, as an example of a material connection, strip 13 is connected to the associated guiding flange 7 by welding or bonding, whereas on the right in the figure, a positive connection is illustrated where the guiding flange has a downwardly extending knob 15 passing through strip 14. To achieve a positive connection, knob 15 has e.g. a mushroom shape with an enlarged head, and strip 14 has holes for receiving knobs 15 whose diameter is smaller than the diameter of the heads of knobs 15. Since strip 14 is a strip of a synthetic material, as mentioned, it has a sufficient elasticity to ensure that the heads of knobs 15 enlarge the aforementioned holes while passing therethrough and that the latter subsequently contract again.

FIGS. 3 and 4 show a second embodiment of a loading device by which a frictional connection of the weld-in closures 4, in this case to a single strip 12, is achieved. More specifically, FIG. 3 shows a view sectioned along line III-III in FIG. 4 whereas FIG. 4 shows a top view. Here, corresponding openings of strip 12 are pushed over pouring spouts 5. The diameter of these openings is preferably smaller than the outer diameter of weld-in closure 4 in the corresponding area, so that a press fit between strip 12 and weld-in closure 4 results, and more particularly a collar 17 of strip material connects parts 12 and 4, The openings may already be present in strip 12 or may be created in the loading device. In principle, if they have a suitable shape, pouring spouts 5 might be pushed through strip 12 by themselves on application of a pressure.

In this example, guiding rails 10 are designed as relatively thin rails which engage in guiding grooves 8 formed in weld-in closures 4. Instead of two opposite guiding grooves 8, a circumferential guiding groove may be provided, which offers the advantage that packaging bag 1 can be rotated while being retained between guiding rails 10. In the top view according to FIG. 4 it is also seen that strip 12 may be provided with holes 16 arranged at regular intervals in order to be able to feed the strip forward positively and in defined steps, e.g. by means of some kind of gearwheels.

FIG. 5 shows a somewhat different embodiment of the strip according to FIGS. 3 and 4. In this case, holes 16 described with reference to FIGS. 3 and 4 have an oval shape. They may serve as transport aids, as mentioned, but also as orientation aids, e.g. for the control of a device for connecting weld-in closures 4 to strip 12. Alternatively or in addition to holes 16, strip 12 may be provided with embossings, knobs, ribs or applied structures which support the transport, the positioning, the stiffness or the storing of the strip during its entire useful life. As an example of embossings, reinforcing ribs 18 extending in the longitudinal direction of strip 12 are depicted in FIG. 6. Furthermore, strip 12 may have reinforced longitudinal edges 20 on both sides. Also, an opening 19 for receiving weld-in closure 4 is shown in FIG. 5, e.g. in the form of a cruciform incision.

FIG. 7 shows a top view of strip 12 according to a further exemplary embodiment. The latter is also shown in FIG. 8, which shows a schematic cross-sectional view along line VIII-VIII in FIG. 7. Here, in order to receive weld-in closure 4, a round opening 21 is punched out. Strip 12 may be two-layered or tube-shaped, and comprises two lateral chambers 22 that may be pressurized at least on a portion of their length with a fluid, e.g. air, in order to stiffen strip 12. For the same purpose, reinforcing strips 23 may additionally be bonded or welded thereto. Here also, as in the strip according to FIGS. 5 and 6, laterally reinforced edges 20 may be provided.

The measures described with reference to FIGS. 5 to 8 may also be applied in cases where two parallel strips 13, 14 are to be used.

FIG. 9 shows a view sectioned along line IX-IX in FIG. 10 of a third exemplary embodiment of a loading device designed as a welding station in which a weld-in closure 4 of a packaging bag 1 is being connected to two strips 13, 14. FIG. 10 shows a top view of this arrangement. Similarly as in the illustration of FIGS. 1 and 2, weld-in closure 4 is again retained here by its guiding flanges 7 in guiding rails 9 while strips 13 and 14 are resting on guiding rails 9 below guiding flanges 7. Two welding devices 24 are arranged underneath guiding rails 9 and movable in the direction of double arrows 26. Each welding device 24 has a heat transfer element 25 that can be moved through a corresponding opening in guide rail 9 to the respective strip 13, 14 to punctually weld the latter to guiding flange 7. For the protection of packaging bag 1, respective heat protection skirts 27 are arranged between the latter and welding devices 24. At the same time, the skirts may serve to deflect the film layers of packaging bag 1 to a position as indicated by reference numeral 1 in FIG. 10 and thus make room for the welding operation underneath guiding flanges 7.

After connecting packaging bags 1 to strip 12 or to strips 13, 14, respectively, the thus formed transport unit is further transported out of the loading device and either laid down in a logistics container for storage and further transport or directly transferred to a filling installation. The placement in a logistics container is preferably carried out automatically by a corresponding placement device, more particularly such that packaging bags 1 are laid down in a scale-like manner and thus take up a minimum volume inside the logistics container. To this end, the placement device may be provided with conveyor and/or guiding means for strip 12 or strips 13, 14, respectively, these means and the logistics container being movable relative to each other. Tests have shown that in this manner about twice as many packaging bags 1 fit into a logistics container as in the method mentioned in the introduction where the packaging bags are received in tracks. In tests conducted by the applicant, transport units of up to several tens of thousands of packaging bags were formed. Due to the placement in layers, the end of strip 12 or of strips 13, 14 will ultimately be located at the top of the full logistics container. When the described placement method is used, the logistics container can have nearly any desired shape. Thus, not only cubic containers can be used as until now, but also e.g. round containers or even bags.

To unload the transport unit at the destination, all that is required is to seize the end of strip 12 or of strips 13, 14, respectively, that was laid down last, and to feed it e.g. to an unloading device from where it will be further transported, e.g. to a filling installation. The unloading device may also be equipped with conveyor and/or guiding means, these means and the logistics container possibly being movable relative to each other here also.

If the packaging bags 1 connected to strip 12 or to strips 13, 14, respectively, are directly forwarded to further processing steps, e.g. in a filling installation, it is an advantage that packaging bags 1 will arrive there in a defined orientation and at constant intervals so that no intervention by personnel is required. The mentioned further processing steps may be carried out in a different room while the transport may e.g. take place in a tube or tunnel in order to meet the hygienic requirements.

FIGS. 11 and 12 show a first exemplary embodiment of a separating device for separating strips 13, 14 from guiding flanges 7, FIG. 12 showing a top view and FIG. 11 a view sectioned along line XI-XI in FIG. 12. Here also, as in the loading station described above, two parallel guiding rails 9 are provided on which guiding flanges of weld-in closures 4 are slidably guided and supported. Strips 13, 14, of which only strip 14 is visible in FIG. 11, are led through a slot 30 in guiding rails 9 and guided away in the direction of arrow 32. The weld-in closure on the left in the Figure is thus entrained in the direction of arrow 29, and strips 13, 14 are deflected around a relatively sharp edge 31 whereby the punctual welded connections between guiding flanges 7 and strips 13, 14 are torn apart.

FIGS. 13 and 14 show a second exemplary embodiment of a separating device for separating strips 13, 14 from guiding flanges 7, FIG. 14 showing a top view and FIG. 13 a view sectioned along line XIII-XIII in FIG. 14. The design according to this embodiment is very similar to the embodiment previously described with reference to FIGS. 11 and 12. Therefore, identical parts denoted by identical reference numerals will not be described again. In this embodiment also, each guide rail 9 has a respective slot 36 through which strip 13, 14 is guided in the direction of arrow 37 but not deflected as sharply as shown in FIG. 11. A punching tool 33 is arranged in a guide bush 35 and movable up and down in the direction of double arrow 34. The punctual weld joints on guiding flanges 7 are thereby punched out in such a manner that a remainder 38 of strip 13, 14 remains on guiding flange 7, as seen in FIG. 13 on the right.

FIGS. 15 and 16 show an exemplary embodiment of a transport aid, FIG. 15 showing a top view and FIG. 16 a view in the direction of arrow XVI in FIG. 15. In particular, such a transport aid serves for relieving strips 12, 13, 14 when packaging bags 1 are fed forward by these strips. However, it may also be used in a loading station to feed packaging bags 1 forward at defined intervals and in a defined orientation prior to being connected to strip 12 or to strips 13, 14, respectively. Pouring spouts 5 of packaging bags 1 are seized by a gripper 39 that is in turn arranged on a transport element 40 and connected thereto. The transport element may be a flexible band conveyor or a plate-shaped body that is connected to further similar transport elements in the manner of a chain. A recess 41 is provided for the partial passage of weld-in closure 4.

FIG. 17 shows a schematic perspective drawing of an installation for filling packaging bags 1 and at the same time a further embodiment of a separating device for separating packaging bags 1 from a strip 12. Strip 12 and the manner in which packaging bags 1 are connected thereto have been described above with reference to FIGS. 3 and 4. The transport unit formed of strip 12 and packaging bags 1 connected thereto has been laid down in a logistics container 42, and to unload the transport unit, its end that was laid down last is unloaded first and guided to the installation, which movement may be assisted by a pair of conveyor rollers 43. By a filling device 44, symbolically indicated in the Figure by a funnel, packaging bags 1 are filled with a liquid or pasty content. Here another substantial advantage of the present invention becomes apparent, namely that due to the connection of weld-in closure 4 to strip 12 or to strips 13, 14, respectively, the opening of weld-in closure 4 is freely accessible and thus allows directly filling the packaging bag 1 therebelow in a hygienic manner. Subsequently, the filled packaging bags 1 are forwarded to supporting rails 28 on which they rest and slide with their guiding flanges 7. Strip 12 is upwardly deflected by deflecting rollers 46 and thereby separated from the weld-in closures and wound up on a reel 45. Now the packaging bags 1 on supporting rails 28 can be closed by means of non-represented caps, e.g. in the form of screw caps or snap-on caps. This may be done before or after separating the packaging bags 1 from the strip or the strips, respectively. Also, safety tests, weight checks, inspections of the optical appearance etc. of packaging bags 1 can be carried out in this phase.

Furthermore, the connection of packaging bags 1 to strip 12 or to strips 13, 14, respectively, can be used for the logistics of the filled packaging bags down to the end user. Thus, for example, correspondingly equipped automatic units can separate a particular packaging bag on demand. Furthermore, multipacks may e.g. be prepared which comprise multiple packaging bags 1 having the same or different contents. In this case, strip 12 or strips 13, 14, respectively, may be used for marking the multipacks by a colored design and/or printing.

The exemplary embodiments show possible realizations of the invention, but it should be noted at this point that the invention is not limited to the depicted particular embodiments thereof. Instead, individual components described with reference to a particular embodiment may e.g. be used in another embodiment and may possibly replace a corresponding component described with reference to that embodiment. Therefore, all conceivable embodiment variants resulting from combinations of individual details of the depicted and described embodiment variants are also encompassed in the scope of protection.

Ultimately, as a matter of form, it should be pointed out that for a better understanding of the construction of the described components, the latter are illustrated schematically and not true to scale.

LIST OF REFERENCE NUMBERALS

1 packaging bag

2 film layers

3 weld seam

4 weld-in closure

5 pouring spout

6 pouring opening

7 guiding flange

8 guiding groove

9 guiding rail

10 guiding rail

11 gap

12 strip

13 strip

14 strip

15 knob

16 holes

17 collar

18 reinforcing rib

19 opening

20 edge

21 opening

22 chamber

23 reinforcing strip

24 welding device

25 heat transfer element

26 double arrow

27 heat protection skirt

28 supporting rails

29 arrows

30 slot

31 edge

32 arrow

33 punching tool

34 double arrow

35 guide bush

36 slot

37 arrow

38 remainder

39 gripper

40 transport element

41 recess

42 logistics container

43 feed roller pair

44 filling device

45 reel

46 deflection rollers 

1. Method for transporting packaging bags for liquid or pasty products having a weld-in closure with a pouring opening where a number of packaging bags are connected by their weld-in closures to at least one flexible strip to form a transport unit, wherein the packaging bags are delivered to a loading device where they are supported by their weld-in closures on supporting and guiding means and moved along these supporting and guiding means, and in that at least one strip is guided along these supporting and guiding means and connected there to the weld-in closures.
 2. Method according to claim 1, wherein the weld-in closures are connected to the at least one strip in such a manner that the pouring opening is freely accessible, and the pouring opening and the portions of the packaging bag opposite the latter are located on opposite sides relative to the plane of the at least one strip.
 3. Method according to claim 1, wherein the weld-in closures are connected to the at least one strip; in a frictional or positive manner in that a portion of the weld-in closure adjacent to its pouring opening is pushed through the at least one strip.
 4. Device according to claim 1, wherein the weld-in closures are materially connected to the at least one strip in that a portion of the weld-in closure adjacent to its pouring opening is welded or bonded to the at least one strip.
 5. Method according to claim 1, wherein the at least one strip comprises at least one layer of a plastic film, preferably of polyethylene, polyethylene terephthalate, polypropylene, or polyamide.
 6. Method according to claim 1, wherein the at least one strip has reinforcing means arranged therein, preferably in the form of longitudinal ridges, edge reinforcements, or chambers capable of being pressurized by a fluid.
 7. Method according to claim 1, wherein the weld-in closures are connected to two parallelly guided strips.
 8. Method according to claim 7, wherein weld-in closures are supported on the supporting and guiding means by guiding flanges or guiding grooves arranged on the former.
 9. Method according to claim 1, wherein transport units each comprising at least a hundred packaging bags are laid down in logistics containers in layers, for which purpose guiding means of the placement device and of the logistics containers are preferably moved relative to each other.
 10. Device for transporting packaging bags for liquid or pasty products having a weld-in closure with a pouring opening, comprising a loading device for connecting at least one flexible strip to the weld-in closures of a number of packaging bags to form a transport unit, wherein the loading device comprises supporting and guiding means for the weld-in closures.
 11. Device according to claim 10, wherein the supporting and guiding means consist of two parallel rails between which a gap for the passage of a portion of the weld-in closures is provided.
 12. Device according to claim 10, wherein the loading device includes welding means for welding the at least one flexible strip to the weld-in closures.
 13. Device according to claim 10, further comprising a placement device for placing transport units in logistics containers, which is preferably provided with guiding means for the transport units and with means for moving the guiding means and the logistics containers relative to each other.
 14. Device according to claim 13, further comprising a pickup device for picking up transport units laid down in logistics containers, which is preferably provided with guiding means for the transport units and with means for moving the guiding means and the logistics containers relative to each other.
 15. Device according to claim 10, further comprising a separating device for separating the weld-in closures from the at least one flexible strip. 